1. Field of the Invention
The present invention relates generally to the testing shafts, and more specifically to testing of golf club shafts.
2. Discussion of the Related Art
Currently there are a variety of devices to test the durability of a shaft. Different tests have been designed and developed to filter out shafts that don't have acceptable structural strength. For example, in the golf industry, a commonly used shaft destruction test is the air cannon test, whereby a ball is shot at a golf head at a specified speed until an acceptable impact quantity is reached or there is a catastrophic break (the head is bonded to the shaft as would be in the field). This test requires multiple iterations (often times up to 3000 hits and beyond). Additionally, air cannon tests are time consuming, noisy, require human supervision and are potentially dangerous (essentially since a projectile is launched at high speed toward the club head).
The above-described methods test the structural integrity of a composite golf shaft. At least one problem with these methods and other composite golf shaft testing methods is that all of these tests focus on one singular location or point on the shaft and not at different points of the or the entire circumference. This type of testing can lead to a “false positive” destructive test result. One reason for a “false positive” result is because of composite ply drop offs. Variations in shaft wall thickness caused by ply drop-offs or poor designs can lead to strength variations in the shaft about its circumference.